My car sits for a while often and everytime i start it i get a low battery warning. Last week we has -5 temps and my car started up kind of slow but started i just let it run for 5 mins. today i go to start the car and its in the upper 30's the door wouldnt unlock, got it open and everything was dead. i just was running the car 3 days earlier no probs. should i just leave this car on a 2amp trickle charge all the time.

 

Your battery may be gettign weak? Still have the MB battery or running another brand or smaller amp batter? I use the C6 vet battery and I think auto zone supplier made all those deffective On my 3rd wrranty one in a year.

 

yea mine says mercedes benz on both. like i said i was suprised that it started in the negative weather vs high 30's today going to let it charge over night.

 

Do you have anything plugged into the OBD port? It supplies a constant +12v.

Sometimes I forget to unplug my ELM327 and it does remain on, draining the battery while the car is locked.

 

hmmm just my aeroforce gauge which i didnt have when we had the below zero temps it was being reflashed at aeroforce maybe i need to keep it unplugged when i do not drive it.

 

To be honest, the cold temps are def what is killing the battery. I just had to change out my battery, same issue as you. Car began to start very slowly, until one day it didn't start (after leaving the tire pressure pump plugged in to the power outlet). I jumped it, rode about 1 more week, left down south for 2 weeks, and came back to a fully dead battery. Car didn't even wanna open the doors. My automatic trunk also messed up and wouldn't open anymore (after the car was running, something seemed to mess up the hinge mechanism). But that's a different story. I would suggest you swap out the batt, before it hits you when you need it most.

 

did u fix your sbc ? when I was having sbc problems batt would get low real fast all the time.

 

nope never did that i guess i can look into that as well